1. Field of the Invention
The present invention relates to an electrophotographic photoconductor, and more particularly to an electrophotographic photoconductor where there are little generation of cracks, crystallization of a photosensitive layer, and the like due to the sticking of finger oil or the like.
2. Related Art
Conventionally, as an electrophotographic photoconductor to be used in an image-forming apparatus, an organic photoconductor has been widely used. The organic photoconductor is comprised of a charge generating agent for generating electric charges by light irradiation, a charge transfer agent for transporting charges generated by the charge generating agent, a binding resin that constitutes a layer on which these substances are being dispersed, and so on.
In addition, an image-forming process is carried out on such an organic photoconductor. The process includes the steps of charging the surface of the organic photoconductor (main charging step), forming an electrostatic latent image (exposure step), developing the electrostatic latent image by toner while being applied with a development bias current, transferring a toner image formed from the organic photoconductor to a sheet of transfer paper by a reversal development system (transfer step), and fixing the toner image thereon by heat to form a predetermined image.
Furthermore, the residual toner on the organic photoconductor is removed by a cleaning blade (cleaning step), while the residual charges on the organic photoconductor are eliminated by LED or the like (neutralization step).
However, the conventional electrophotographic photoconductor has problems, such as less endurance as well as low sensitivity.
To solve the problems, a positively-charged monolayer-type electrophotographic photoconductor has been disclosed such that an electrophotographic photoconductor to be employed in a reversal development system uses a certain electron transfer agent together with the addition of a tarphenyl compound to improve gas resistance while reducing the size of a transfer image memory (for example, Patent document 1).
In addition, for improving the positive-charging and repeating properties, a monolayer-type electrophotographic photoconductor containing a certain charge generating agent, a chare transfer agent, and a binding resin has been disclosed such that it is further added with a biphenyl derivative (for example, Patent document 2).
Furthermore, an electrophotographic photoconductor has been disclosed such that a certain stilbene derivative and a polycarbonate resin are used as a hole transfer agent, and a biphenyl derivative and a sebacic acid derivative are also added (For example, Patent document 3).    Patent document 1: JP 2001-242656 A (Claims)    Patent document 2: JP 2000-314969 A (Claims)    Patent document 3: JP Hei6-75394 A (Claims)